Quoting Marko Mäkelä <marko.makela@iki.fi>:
Hi Charlie,
On Tue, Dec 29, 2009 at 09:56:12AM +0000, charlie@cferrero.net wrote:
Quoting svn commit <svn@mkgmap.org.uk>:
Version 1445 was commited by marko on 2009-12-29 09:45:48 +0000 (Tue, 29 Dec 2009)
Hide underground railways. Map railway=abandoned to highway=track.
Out of curiosity, why hide underground railways but not underground roads?
Because, as far as I know, Garmin units do not support railway navigation. Actually, the underground railways are now omitted from the translation altogether; I do not know how to create invisible routeable ways.
The reason why I committed this change is that underground railway tracks tend to be very long and built deep underground, below roads or even residential areas. There is a 30km long harbour tunnel near my home (not completely mapped yet, but I already find it a little confusing to see it on the map). Also, some time ago, I found it confusing to see subway tracks running through a pedestrian area in the centre of Helsinki.
Given that Garmin units do not work deep underground, omitting the underground railways should not hurt navigation. Railways that are visible on the ground can be useful, especially when visiting incompletely mapped areas.
I may create map layers for public transportation routes in the near future. Then I will have to make sure that underground railways do appear on the railway route layer.
If someone knows how to create invisible routeable ways, then we might consider hiding underground roads. I would only do that when a special tag is set, for very long tunnels that go through cities, such as those in Stockholm, Sweden or Brussels, Belgium.
Best regards,
Marko It would be good to create invisible routeable ways for places like this: http://www.openstreetmap.org/?lat=51.512189&lon=-0.117448&zoom=18&layers=B00...
Whilst mapnik renders the Strand Underpass fine, mkgmap creates a nasty looking road going straight through the various buildings. Unfortunately I think that GPS units plot polygons first, then lines, so there's no single-layer solution at the moment. A multi-layer solution is to have: Visible layer, which does not plot highway=* & tunnel=yes Routing layer, which does. This way you don't see the tunnel roads on the map, but you can route through them. -- Charlie